Abstract: In order to reveal the primary reaction mechanism of Meloidogyne incognita infection on photosynthesis effects in eggplant leaves,‘Ziyang Changqie’seedlings, which were planted in pots and inoculated with Meloidogyne incognita, were used to study the changes of chlorophyll fluorescence parameters during its inoculation. The results indicated that the maximal photochemical efficiency (Fv/Fm), actual photochemical efficiency (ΦPSⅡ), and photochemical quenching coefficient (qP) of PSII declined continuously, whereas the non-photochemical quenching coefficient (NPQ) increased continuously with Meloidogyne incognita infection. Furthermore, the turning point of fluorescence parameters change appeared on the 15th day after inoculation, and the change was slow before this timepoint while it was very fast after that. It was showed that the reaction center of photosynthetic systemⅡ(PSⅡ) was damaged owing to Meloidogyne incognita infection. In a word, these parameters can be used as the resistance index to Meloidogyne incognita in eggplant seedlings, and this method was simple, easy, efficient and accurate.